[April, 1886. ELUOTT SOCIETY. 117 



symptoms observed and the result, but we were unable to understand how these 

 parasites had found their way into the heart, as we supposed that they belong- 

 ed to the alimentary canal, and that they could have been in the heart but a 

 short time. Another surprising circiunstance was that but few worms were 

 found in the intestines, and those of small size compared to those found in the 

 heart. 



Unable to find a satisfactory esplanation, we sent a statement of the above 

 facts to Messrs. Munn & Co., Editors of the Scientific American, who took 

 great interest in the case, and gave us, in substance, the following particulars : 



That our statement was of interest, as, in this country, cases such as we de- 

 scribed, are fortunately rare. In China, however, this is not the case. Hun- 

 dreds and even thousands of dogs die in the same diseased condition. The 

 entozoon, which we described, was doubtless ©ne of the Nematode Blood 

 worms, and not an inhabitant of the intestines. The species so fatal to dogs 

 in China and Japan is often appropriately called the "Cruel Threadworm." 

 It is the Fikiria immitis. Some writers refer it to Spiraptera mnguinolenta, 

 but Cattold says that that species "does not gain access to the blood vessels." 

 Dr. Lamprey says that "the hearts of dogs at Shanghai are invariably found 

 to contain these entozoa." The dogs sometimes die suddenly in a fit, and some 

 linger long in great pain. 



They concluded their interesting letter with the statement that the entozoa 

 which we had foimd were of interest on account of the unusual size attained 

 ( 33 centimetres ) as the usual length was only 10 to 12 centimetres. 



Having gained this information, we made a microscopic examination of a fe- 

 male Filaria Immitis, which we had found in the heart, and found the oviducts 

 crowded with eggs and embryos in all stages of development. We also made a 

 special examination of the blood with one of the higher powers of the micro- 

 scope, ( 400 diam. ) and found it crowded with the bodies of parasitic animalculse. 

 In our examination we found only the fully developed worm, which, with the 

 embryos observed in the oviducts of the Filaria immitis examined, convinced 

 us that they are reproduced viviparously, and that the young are afterwards 

 carried along in the circulation. 



In seeking for the origin of this diseased condition of the dog, we learn that 

 in India, where this disease is most prevalent, it is supposed that the animals 

 may have obtained then- parasites from the ova of Ascarides passed by man. 

 It has been asserted that human excrement forms the principle food of dogs 

 in China and India. Presuming the possibilities of the development of the 

 Filaria immitis from the ova of the Ascarides, this would account for the great 

 prevalence of the disease in those coimtries. 



Dr. Lamprey thinks that the presence of this haematozoon is only prejudicial 

 to the canine bearer when the animal is suffering from some other cause, and 

 cites a case where a dog was killed and found to contain over 200,000 of these 

 minute worms, without having previously developed any symtoms of uneasi- 

 ness. Tliis, however, appears very improbable. In the case, for instance, 

 which came to our notice, the dog evidently died from the effects of the para- 

 sitism. 



